Microbes behave and evolve in response to their environment and to properly study them it’s important to simulate common places where microbes gather in great variety. The colon is a well known place where a plethora of lifeforms live rich and pungent lives and where pathogens can develop.

Ian Marcus, a recent PhD graduate from the University of California, Riverside, built a replica human colon, along with a septic tank and simulated groundwater, to study how microbes interact at the macro level. The system was seeded with a “representative” microbial community with a pinch of Escherichia coli O157:H7 in the mix.

Here are the findings from the study abstract in Applied Environmental Microbiology:

The microbial community in the colon was found to have a high percentage of bacteriodetes and firmicutes, while the septic tank and groundwater systems were composed mostly of proteobacteria. The introduction of E. coli O157:H7 into the simulated systems elicited a shift in the structures and phenotypic cell characteristics of the microbial communities. The fate and transport of the microbial community with E. coli O157:H7 were found to be significantly different from those of E. coli O157:H7 studied as a single isolate, suggesting that the behavior of the organism in the environment was different from that previously conceived. The findings in this study clearly suggest that to gain insight into the fate of pathogens, cells should be grown and analyzed under conditions simulating those of the environment in which the pathogens are present.